Expansion of narrowing math built-ins into power instructions

[Florian Weimer]

* Martin Jambor:

> as you might know, Tejas is our Google Summer of Code student working on
> adding built-in functions for some new math functions added in ISO/IEC
> TS 18661.
>
> His next step is to expand "functions rounding result to narrower type"
> (so fadd, fsub and possibly fmul and fdiv described in
> http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2314.pdf) into ISA
> instructions on targets that have such instructions.

Sorry, this might be a silly question, but: How do you plan to recognize
that the fadd/fsub being called is indeed the one from the TS?

Thanks,
Florian